Internal combustion engine



Aug. 23, 1938.

L lr.. GRANT INTERNAL CQMBUSTION ENGINE Filed July 20, 1936, 2Sheets-Sheet l Aug.. 23,` 1938. GRANT INTERNAL COMBUSTION ENGINE FiledJuly 20, 1956 2 Sheets-Sheet 2 Horne y Patented Aug. 23, 1938 UNITEDSTATE PATENT OFFIQE Application July 20,

2 Claims.

My present invention relates to improvements in internal combustionengines of the Diesel type wherein air is supplied to the workingcylinder of the engine and compressed by a compression 5 stroke of thepiston to such a degree that the high temperature of the compressed aircauses combustion when oil is supplied thereto.

It will be understood however that the engine of my invention is alsoadapted for combustion of l `gasoline when an igniting spark is employedtherewith.

In its structure and arrangement the engine, when burning the charge byhighly compressed air, involves multiple, opposed or opposite cylinders,arranged in one or more pairs, one cylinder of each pair on either sideof the main shaft or crank shaft of the engine with coincident axiallines intersecting the shaft at right angles. For convenience ofillustration I have disclosed the use of two opposed cylinders, or onepair of pistons connected with one crank of the shaft, but it will beunderstood that a number of cranks of the main shaft or crank shaft areto be so equipped.

The two working pistons of a pair are rigidly joined for reciprocationin their respective cylinders, and each cylinder is equipped with astationary, inner head or abutment that is located within areciprocating piston, thus providing for a working stroke of the piston,outwardly, or away from the shaft with a consequent pull on the crank inlieu of the usual push against the crank. The strain of the pull isabsorbed at the crank by a transversely slidable crank head intermediatethe pistons, and the force of combustion or expansion of the fuel chargeis imposed against the stationary, interior cylinder head or abutment. Acharge of air is compressed in one cylinder while an expansion orworking stroke is taking place in the other cylinder, and cam-actuatedvalve operating means are employed with each cylinder for controllingthe supply of air thereto. 'I'he charges of oil are supplied to theinterior of the working cylinders, or combustion chambers, through theinterior heads of the cylinders which communicate with means forsupplying the oil for fuel.

By this arrangement of parts in the engine, a compact and powerfulengine-unit is provided in which the parts operate smoothly, and as theconstruction is simple, the parts may readily be manufactured andassembled, repairs and replacements may be made with facility, and highefficiency is attained in the operation of the engine.

1936, Serial No. 91,485

(Cl. 12S-50) The invention consists in certain novel combinations andarrangements of parts as will hereinafter be more fully set forth andclaimed. In the accompanying drawings I have illustrated one completeexample of the physical embodiment of an engine-unit, wherein the'partsare combined and arranged according to the best mode I have thus fardevised for the practical application of the principles of my invention.

Figure 1 is a sectional view of an engine-unit with the upper air intakevalve closed and the lower intake valve open, and the pistons inapproximately neutral position.

Figure 2 is an enlarged detail vertical sectional view of a portion ofthe upper cylinder with its air intake valve closed and the piston atthe end of its compression stroke with the compression chamber open tothe combustion chamber.

Figure 3 is a detail sectional View of one of the interior, stationary,cylinder heads, detached, and showing the valve-controlled oil supplyducts.

Figure 4 is an enlarged horizontal sectional view at line 4 4. of Figure2, showing the tangential arrangement of the inner compressed air portsfor creating turbulency in the combustion chamber.

Figure 5 is a detail sectional view similar to Figure 1 but with thecrank shaft turned 9!! degrees, with the upper piston charging itscornbustion chamber, and the lower piston at the upper end of itsworking stroke.

Figure 6 is an enlarged detail view in elevation showing one of the pairof rigidly joined werking pistons, and the relation thereto of a dottedfixed or stationary head, together with details of the transverselyslidable crank head.

Figure 7 is a detail cross section at line 1 1 of Figure 5 showing theactuating cam for operating the air valves.

Figure 8 is a d-etail sectional view at line 8 8 of Figure 6, looking upinto the piston and showing in section the attaching legs for theinterior piston or cylinder head.

In the construction and assembly of the illustrated engine-unit I employa cylindrical housing l which is held stationary or fixed in suitablemanner, and the crank shaft 2, which passes longitudinally through thehousing, is journaled in bearings as 3, so that the crank will turn inthe crank case or chamber 5 of the housing.

The fixed housing is fashioned with a pair of diametrically arrangedcylindrical extensions 6 and l', and the opposed cylinders 8 and 9 withcoincident axes are bolted to the outer ends of these extensions.

The inner ends of the cylinders open to the interior of the crank caseor housing I, while the outer heads or ends of the cylinders are closed,but provided with air pipes and air intake ports III and Ilrespectively, and air intake valves l2 and I3 for controlling admissionof air to the cylinders. These valves are spring-closed, and they areopened at the proper instant in the cycle of operation of the engineunit by an actuating cam I4 on the crank shaft and located within thecrank case. The cani actuates, alternately, the valve-operating rods I5,I5 and these rods operate the push levers or rocker arms ifi to open thevalves against the tension of the springs Il, which springs close thevalves during the operating cycle. In addition to the main intake portsfor air at the outer ends or heads oi the two cylinders, these cylindersare each provided with an annular series of longitudinally extendinggrooves I8 in the faces of their walls, forming transfer ports for airfrom the compression chamber into the combustion chamber, as will bedescribed.

As best seen in Figure 6 a rectangular block or crank head IS isjournaled on the crank fi, within the cra-nk case, and as the crankturns in this head, the latter reciprocates transversely oi the engineunit and of the crank shaft. The rcciprocating movement of the slidehead is guided between ilanges or ways 2t! and 2l, and at their fourcorners these rectangular or guideways are bolted together at 22, theWays being spaced apart as best seen in Figure 6 for frictionalengagement with the opposite faces of the Slide-head or crank head I9.These flanges or Ways 2l] and 2I are each fashioned integral with orrigid with a web, as 23 and E11 respectively, and the webs are providedwith outer attaching plates 25 that are bolted to and across the ad- 1joining inner ends of the two cylindricai hollow pistons 26 and 2T. Theopposed piston-unit thus includes the pair of spaced pistons to whichare attached the spaced I-plates 23 and 2li, and these plates arerigidly joined by the tie bolts 22. The crank head IB reciprocatestransversely between the guides and of course revolves with the crank,while the opposed piston unit reciprocates rectilinearly under thesuccessive impulses of combustion in the cylinders.

As best seen in Figure 2 each hollow cylindrical piston is fashionednear its outer end 'with a transverse web or depressed head 2li which.forms an explosion chamber 29 within the inner portion of the piston,and a compression charnber 3F! in the outer end of the piston whichcompression chambers are closed by the valve-ends of the cylinders. Thisdepressed head is fashioned with an annular series of ports 3E extendingtangentially through the circular wall of the piston to affordcommunication between the transfer ports I8 of the cylinders and theinteriors of the explosion or combustion chambers 29 of the pistons.When the air intake valve is opened air flows into the compressionchamber and on the outward compression stroke of the piston this chargeof air is compressed and forced down through the transfer ports to, andthrough the tangential ports 3i, and this tangential arrangement of theports 3I causes a whirling movement or turbulency of the incoming air toinsure a perfect blending with the fuel oil which also is introduced tothe combustion chamber.

At a suitable location near the inner ends of the cylinders an annularseries of exhaust ports 32 is provided in the wall of each cylinder, for

exit of spent gas, and the skirt portion of each piston is provided witha complementary annular series of exhaust ports 33 adapted to registerwith ports 32, whereby exhaust or spent gases are displaced irom theinterior of the combustion chamber, and these exhaust gases are disposedof through the annular, exterior exhaust manifold 34 that surrounds eachof the stationary cylinders. In Figure 5 spent gas is being expelledfrom the combustion chamber through the registering exhaust ports, bythe incoming air from the compression chamber.

Within the skirt portion, or inner open end of each of the opposedpistons is located a fixed abutment, as 35 and 35, each of which forms ahead that is stationary, and the combustion chamber in each cylinder isdefined between one of these stationary heads and the depressed head ofa` piston. The combustion chambers are thus provided with varyingcapacities, as are also the compression chambers 3l) due to the relationof the movable, depressed head 28 to the valve-end or head of eachcylinder.

The fixed abutments, as best seen in Figure 3, are solid cylindricalheads with tapered or beveled edges 3l to form annular spaces formovement of exhaust gases to the exhaust ports, and each of these headshas a pair of diametrically arranged legs 38 hanged at 39 for bolting tocomplementary flanges of the crank case. These legs are arcuate in crosssection and they project from their respective heads through theextensions 6 and I of the crank oase and as they are spaced within thebounds of the cylindrical skirts of the pistons, the legs do notinterfere with the reciprocating movements of the pistons.

The interior face of each stationary head or abutment is provided withan oil inlet port 4U forming a valve seat for the spring closed valve 4Iwhich is operatively mounted in the head, and an oil supply conduit orduct 42 extends from the valve seat or port, through the head and downthrough one oi the legs of each head as indicated in Figure 3, and asuitable pump or injector (not shown) is employed to force the oil pastthe spring closed valve 4I into the combustion chamber. The oil thusentering the cornbustion chamber encounters the whirling currents ofcompressed air and the oil is thoroughly atomized to facilitate burningor combustion of the charge. The combustion and expansion of the chargeis directed against the stationary abutments or heads and the depressedheads of the pistons, and the expansion of gas causes an outward,working, stroke of the piston. The outward movement of the piston istransmitted through a web (23 or 26!) to the transversely slidingcrank-head and then to the crank, and the composite movement of theslide head, i. e. rotary and reciprocating turns the crank.

As before stated, in the cycle of operation, one piston compresses acharge of air while the other piston is being red, and the compressingand ring of the charges alternates in the opposed cylinders.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent is:

1. In an internal combustion engine of the opposed axiallyalined-cylinder type, the combination with an intermediate crank caseand crank shaft, and a transversely movable crankhead on the shaft, of apair of rigidly connected hollow reciprocating pistons connectedwith thecrank head, a stationary abutment located in the inner end of eachpiston, and spaced legs on each abutment rigidly attached to the crankcase.

2. In an internal combustion engine, the combination with a pair of xed,spaced axially alined cylinders each having air ports opening into theirouter ends, of a pair of rigidly joined hollow pistons reciprocable inthe cylinders, said pistons each having a depressed head `forming acompression chamber at its outer end, a xed abutment in the inner end ofeach piston, each abutment having a fuel inlet-port and a valvetherefor, said abutments each having spaced supporting legs and one ofsaid legs having a fuelsupply passage extending through the abutment toan inlet-port.

LLOYD L. GRANT.

